1,728 research outputs found
Testing for Stock Market Contagion: A Quantile Regression Approach
__Abstract__
Regarding the asymmetric and leptokurtic behavior of financial data, we propose a new
contagion test in the quantile regression framework that is robust to model misspecification. Unlike conventional correlation-based tests, the proposed quantile contagion test allows us to investigate the stock market contagion at various quantiles, not only at the mean. We show that the quantile contagion test can detect a contagion effect that is possibly ignored by correlation-based tests. A wide range of simulation studies show that the proposed test is superior to the correlation-based tests in terms of size and power. We compare our test with correlation-based tests using three real data sets: the 1994 Tequila crisis, the 1997 Asia crisis, and the 2001 Argentina crisis. Empirical results show substantial differences between two types of tests
Temperature- and magnetic-field-dependent resistivity of MgB2 sintered at high temperature and high pressure condition
We report the temperature- and magnetic-field-dependent resistivity of MgB2
sintered at high temperature and high pressure condition. The superconducting
transition width for the resistivity measurement was about 0.4 K, and the
low-field magnetization showed a sharp superconducting transition with a
transition width of about 1 K. The resistivity in the normal state roughly
followed T^2 behavior with smaller residual resistivity ratio (RRR) of 3 over
broad temperature region above 100 K rather than reported T^3 behavior with
larger RRR value of ~ 20 in the samples made at lower pressures. Also, the
resistivity did not change appreciably with the applied magnetic field, which
was different from previous report. These differences were discussed with the
microscopic and structural change due to the high-pressure sintering.Comment: 2 pages, 3 figures. Accepted by Physica
Evaluation of fermented whole crop wheat and barley feeding on growth performance, nutrient digestibility, faecal volatile fatty acid emission, blood constituents, and faecal microbiota in growing pigs
This study was conducted to determine the effects of feeding diets with fermented whole crop wheat (FWW) and fermented whole crop barley (FWB) on growth performance, nutrient digestibility, blood constituents, faecal volatile fatty acid (VFA) emission and faecal microbiota in growing pigs. A total of 200 growing pigs were randomly allotted to five treatments with eight replicates per treatment and five pigs per replicate. Dietary treatments consisted of i) CON (basal diet), ii) 0.5% FWW (CON + 0.5% fermented whole crop wheat), iii) 1.0% FWW (CON + 1.0% fermented whole crop wheat), iv) 0.5% FWB (CON + 0.5% fermented whole crop barley), and v) 1.0% FWB (CON + 1.0% fermented whole crop barley). The digestibility of total dietary fibre was significantly higher in pigs fed FWW diets. The faecal emissions of VFA of pigs fed the fermented treatments was increased significantly compared with CON. Concentrations of cortisol and triglyceride in blood of pigs fed 1.0% FWW were significantly lower than pigs fed CON diets. The pigs fed 1.0% FWB diets had a significantly decreased level of total cholesterol in blood compared with CON. In conclusion, the current results indicated that diets supplemented with FWW and FWB could increase faecal VFA emission and reduce concentration of triglyceride and cortisol, while 0.5% and 1.0% FWW had no negative effects on growth performance, and could increase digestibility of dietary fibre in growing pigs.Keywords:Ā Dietary fibre, faecal short-chain fatty acid emissions, fermented feed, serum parameter, swin
Structure Formation, Melting, and the Optical Properties of Gold/DNA Nanocomposites: Effects of Relaxation Time
We present a model for structure formation, melting, and optical properties
of gold/DNA nanocomposites. These composites consist of a collection of gold
nanoparticles (of radius 50 nm or less) which are bound together by links made
up of DNA strands. In our structural model, the nanocomposite forms from a
series of Monte Carlo steps, each involving reaction-limited cluster-cluster
aggregation (RLCA) followed by dehybridization of the DNA links. These links
form with a probability which depends on temperature and particle
radius . The final structure depends on the number of monomers (i. e. gold
nanoparticles) , , and the relaxation time. At low temperature, the
model results in an RLCA cluster. But after a long enough relaxation time, the
nanocomposite reduces to a compact, non-fractal cluster. We calculate the
optical properties of the resulting aggregates using the Discrete Dipole
Approximation. Despite the restructuring, the melting transition (as seen in
the extinction coefficient at wavelength 520 nm) remains sharp, and the melting
temperature increases with increasing as found in our previous
percolation model. However, restructuring increases the corresponding link
fraction at melting to a value well above the percolation threshold. Our
calculated extinction cross section agrees qualitatively with experiments on
gold/DNA composites. It also shows a characteristic ``rebound effect,''
resulting from incomplete relaxation, which has also been seen in some
experiments. We discuss briefly how our results relate to a possible sol-gel
transition in these aggregates.Comment: 12 pages, 10 figure
Effects of various additives to enhance growth performance, blood profiles, and reduce malodour emissions in growing pigs
Experiment 1 was a feeding trial in which 75 (Landrace ā
¹ Yorkshire) ā
¹ Duroc pigs with average initial bodyweight (BW) of 26 Ā± 1 kg were used. It was assigned to three pigs/pen and five pens/treatment. Experiment 2 was a metabolic trial in which 25 (Landraceā
¹Yorkshire)ā
¹Duroc pigs with average initial bodyweight (BW) of 36 Ā± 1 kg were used. The basal diet consisted of maize (57.71 %), soybean meal (32.45 %), and wheat bran (5 %). Treatments consisted of i) CON (control diet); ii) OE (organic acid + essential oils) (Aviplus-SĀ®), that is, CON + 0.05 % OE; iii) OC (organic charcoal) (Olga BlackĀ®), that is, CON + 0.1 % OC; iv) AE (anise extracts) (RESQĀ®), that is, CON + 0.015 % AE; and v) PB (probiotics) (BonvitalĀ®), that is, CON + 0.1 % PB. Average daily gain (ADG) and gain/feed ratio (G : F) were significantly higher in the OE and AE groups than in the others. Average daily feed intake (ADFI) for OE, OC, and AE treatments was significantly higher than that for CON and PB treatments. Dry matter (DM) digestibility was significantly higher in AE than CON. Crude protein (CP) was significantly higher in OE, AE, and PB than CON. CON and other treatments did not cause significant differences in blood l-density lipoprotein (LDL), and glucose. NH3 emissions were significantly lower in all treated groups than in CON. Among the treatments, NH3 emissions were lowest in OE and AE. H2S emissions were significantly lower in OE, AE, and PB than in CON. Among the treatments, OE and AE were most effective at reducing H2S emissions. The emissions of volatile fatty acids (VFAs) showed no significant difference between treatments and CON. In conclusion, this experiment was shown to be more effective on growth performance, malodour emission, blood profiles, and nutrient digestibility in OE and AE than other additives.Keywords: Digestibility, feed, influence, odour, supplementation, swin
REMOVED: Preparation of Nanofiltration Membranes using Solāgel Transition of Organic Molecular Networks in their Phaseāseparating Mixtures with Linear Polymers
This article has been removed: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy).This article has been removed at the request of the Executive Publisher.This article has been removed because it was published without the permission of the author(s)
Partially spin polarized quantum Hall effect in the filling factor range 1/3 < nu < 2/5
The residual interaction between composite fermions (CFs) can express itself
through higher order fractional Hall effect. With the help of diagonalization
in a truncated composite fermion basis of low-energy many-body states, we
predict that quantum Hall effect with partial spin polarization is possible at
several fractions between and . The estimated excitation
gaps are approximately two orders of magnitude smaller than the gap at
, confirming that the inter-CF interaction is extremely weak in higher
CF levels.Comment: 4 pages, 3 figure
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